Control device for boilers



Nov. 14, 1939. E. M. FRANKEL ET Al.

CONTROL DEVICE FOR BOILERS Filed Jan. l5, 1938 2 Sheets-Sheetl l ATTORNEY Nov. 14, 1939. E. M. FRANKEI. Er Al. 2.179.782

CONTROL DEVICE FOR BOILERS Filed Jan. l5, 1958 2 Sheets-Sheet 2 CONTROLC/RfU/r 440 Pkw/ER owj Z67 28 rfv INVENTORS Li/,KCA I 'fawn/e0 f7.Henn/Kfz. f

A@ T//ae Paas/n ATTORNEY Patented Nov. 14, 1939 Edward M. Frankel,Cedarhnrst, Mld, Arthur Fallait, New York, N, Y.. assi iors to WestVirginia inlp and llaper Company, New York, lil. Y., a corporation ofDelaware Application January l5, 1938, Serial lilo. li

(Cl. 21B-8i by circuit 22 provided with a manually actuated switch 23and by an automatic switch 24, re-

laizns.

Our present invention relates to control systems for electric boilers,particularly those adapted 'for the heating or evaporating of diphenylor sponsive to a predetermined maximum of any other substances boilingat high temperature. desired iable, e` temperature 01 DFESSlllc. 5Boilers of this type are useful in heating systems .ductcl 2tadditionally provided with a depending upon the supply oi a heatingvapor as magnetic switch 25 operated by circuit 26 and for example thatof diphenyl, the vapor of which an automatic switch Similarly, conductorI9 is circulated through various heating spaces and a magnetic switch3B, circuit 3l, and manthen returned as liquid to the boiler. Becauseswitch There is a familiar law governof the nature of such use it ishighly importantl fA three-phase circuits that when one leg of hat thevapor be furnished at a uniform temas lor example the conductor 25, isperature as otherwise the benefit of applying imerrupted, the powerinput is thereby halved. heat by means of a vapor is largely lost. Wehave found Jthat the automatic control of Our invention is particularlyadapted for use such leg of the three-phase system affords a Hconnection with a three-phase power circuit control. means of greataccuracy. To accomemployed as the source of heat, but is not limitedplish this we provide for periodic cutting in and thereto. cutting outof the coil A, advantage being taken The principal object of theinvention is, thereoi the large heat capacity of the boiler and confore,to provide for accurate and automatic contents to absorb the heatcontributed by coil A trol oi the heat input to the boiler or heaterduring the heating period and distribute it durwhereby the heatfurnished the system to be ing the non-heating period whereby thetimeheated by means of the vapor can be very ac- 'emperature curve inrespect to the vapor furcurately controlled. nished by the boiler is forall practical purposes Still further objects of the invention and variastraight line. ons advantages thereof will be apparent as the Toaccomplish this control we have devised description proceeds and thenovel features will the following apparatus: 35, Fig. 1, denotes a bepointed out in the appended claims. panel board having an operatingwheel 36 at- The invention will be best understood by reftached to ashaft 3l journaled in a bracket 38 erence to the following detaileddescription taken attached to the rear of said journal. A shaft 40 withthe annexed drawings, in which is also mounted in the rear of the panelin jour- Fig, is a plan View of an illustrative embodinals di and l2attached to brackets 43, 44, rement oi our improved control device;spectively. Loosely mounted on said shaft but Fig. 2 is a view ofcertain operating mechakeyed thereto is a cylinder 45 having a nonnismsof said control device; truncated portion 423, a portion 41 truncated as3,', Fig` 3 is a fragmentary view on a reduced by an obliquely disposedplane. Cylinder 45 has scale as seen from the left of Fig. 2; an endflange 4S, engaging which are fingers 49,

Fig. ll is a diagram of the control circuits for @t attached to aslidable rack 50, said rack enheating elements of the electric type;gaging gear 5i attached to shaft 31. When the wheel is turned, the rack50, and conse- 5 is a View in vertical elevation of the entire electricheating unit to which the invenquently the cylinder 45, is moved back orforth tion is applicable; along the shaft llt. The shaft 4U is driven byan Fig. 6 shows the invention as applied to oilelectric motor 52 oiconstant speed type through burner heating. shaft 53 and gear reductionbox 54. Journaled Referring to Fig. 5, the heating elements there insupport 55 is a lever 5'! having a follower 58 shown are divided intothree circuits, A, B and C, which is adapted to follow the curvedsurface of cor isting of coils of resistance ribbon I and the rollAttached to the end of lever 51 is connected by means of conductors il,l2, I3, I4 link 59 which connects with a switch generally denoted byttl. Switch 65, which is of convenior three-phase operation (see alsoFig. 4), the speciiic details ci the boiler, with which the prestionaldesign, consists of a lever 6i carrying a mercury cell 552, said lever lengaging a shield ent awdicaticn is not concerned, being disclosed inour o-pending application, Serial No. 70,328, G52 carried by togglespring 64. In order further illed arch 193. Truce-phase current iscontrol the movement of lever 6I, the same boiler b means of conductorsis attached to compression spring 65, the ten- 5.5 with a magneticallyoperated switch Il operated sion of which is regulated by a screw 66.The operation of the control device Will now be eviand such conductorsbeing provided dent. When the follower 58 is in contact with the curvedsurface of the roller 45, the switch G is in the position shown in Fig.2, in which the mercury cell connects the leads 68 and 69, therebyactuating the control circuits 26 to cut in the coil A. When, however,the cut-out portion of the cylinder 45 comes in contact with thefollower 5S, the spring 65 acts to tilt the lever El downwardly pastdead center of the toggle to the off position. When the cylinder ismoved to the right of Fig. 1, by turning the Wheel 36 a greaterproportion of the curved surface is presented to the follower 58 and thecoil A is cut in for a longer time. Should it be desired to keep thecoil cut in for an indefinite period, the cylinder d5 is moved until thenon-truncated portion 4G is in contact With the follower 58. When thecylinder i5 is moved to the extreme left, Fig. 1, the coil A will be outout for an indefinite period.

In the normal operation of the device, the operator has before him arecording chart 1l), Fig. 3, of whatever variable in the system isdesired, i. e., temperature or pressure, which variable is iniiuenced bythe operation of the boiler. If the pointer deviates from the desiredvalue, he manipulates 'the wheel il@ accordingly. Or, the device may berendered fully automatic in operation by known means not shown.

In Fig. 6 we have indicated diagrammatically the application of ourinvention to a boiler which is oil or gas fired. Here a burner 'l5 isprovided which is adapted to run continuously, while burner it? isadapted for intermittent operation. Each burner is controlled through anelectric circuit, shown, as is customary in the art, that for burner 'i6being denoted Tl and having therein a control device 18, the same asillustrated in Figs. l, 2 and 3 and the operation of which serves to cutin and out of operation said burner 16, For each circuit there isprovided a hand switch 'iS and Sil, respectively.

While we have described our improved embodiments in considerable detail,it is understood that we have done so by way of example only and thatvarious chan-ges will occur to those skilled in the art without eitherdeparting from the spirit of the invention or the scope of the appendedclaims.

We claim:

l. in a vapor heating system, a boiler, electric heating units thereinadapted for three-phase operation and automatic means responsive to thetemperature of said system for automatically cutting and cutting out oneleg of the threephase connections to control the average temperature inthe system.

2. In an electric boiler, three electric resistance units, correspondingpoles of said units being joined together and corresponding poles beingrespectively joined to the poles of a three-phase circuit, and automaticmeans for making and breaking one of said three-phase connectionsthereby varying the electrical input and controlling the averagetemperature of the boiler.

3. In an electrical resistance boiler, a plurality of heating unitsconnected for three-phase operation and means for controlling theelectrical input to said boiler comprising a device for interrupting oneof said three-phase circuits at periodic times and means for varying theduration ci each interruption.

EDWARD M. FRANKEL. ARTHUR POLLAK.

